{"id":"CVE-2025-53971","aliases":["EUVD-2025-25413","GHSA-4276-cm8c-788h","GO-2025-3902"],"status":"published","title":"Channel and Team Membership APIs inadvertently allow loss of Member privileges.","description":"Mattermost versions 10.5.x \u003c= 10.5.8, 9.11.x \u003c= 9.11.17 fail to properly validate authorization for team scheme role modifications which allows Team Admins to demote Team Members to Guests via the PUT /api/v4/teams/team-id/members/user-id/schemeRoles API 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Advisory","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-53971","tags":["advisory"]},{"url":"https://pkg.go.dev/vuln/GO-2025-3902","tags":["web"]},{"url":"https://github.com/advisories/GHSA-4276-cm8c-788h","tags":["advisory"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/53xxx/CVE-2025-53971.json","tags":["advisory"]},{"url":"https://github.com/mattermost/mattermost","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2025-53971","title":"Channel and Team Membership APIs inadvertently allow loss of Member privileges.","description":"Mattermost versions 10.5.x \u003c= 10.5.8, 9.11.x \u003c= 9.11.17 fail to properly validate authorization for team scheme role modifications which allows Team Admins to demote Team Members to Guests via the PUT /api/v4/teams/team-id/members/user-id/schemeRoles API 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